Annealing-box bottom



Dec. 4 1923. 1,476,526

a. F. L EHMAN ANNEALING BOX BOTTOM Filed March 14, 1922 r. 'A w A; L m rE 1L 1 n he; i

I j s vwos Fetented fies. 4 l23.

IRVIN F. LEEMAN, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO BLAW-KNOXCOMPANY, OF BLAWNOX, PENNSYLVANIA, A CORPORATION OF NEW JERSEY.

ANNEALINGz-BOX BOTTOM.

Application filed March 14, 1922. Serial No. 543,572.

and useful Improvement in Annealing-Box.

Bottoms, of which the following-is a full, clear, and exact description.

The present invention relates to annealing box bottoms. The box bottomis corrugated and thereby secures certain important and novel advantagesas hereinafter described.

In the drawings,

Figure 1 is a plan view;

Figure 2 is a section along the line 11-11 of Figure 1 and alsoindicates in dotted lines the box;

Figure 3 is a section along the line IIIIII of Figure l; and

Figure 4 is a section along the line TVIV of Figure 1.

Referring to the illustrated embodiment of the invention, the annealingbox bottom consists of a single integral sheet 1 of steel ofsubstantially uniform thickness throughout and having the corrugations 2and 3 formed therein. The sheet may be made of sheet steel in which thecorrugations are pressed, or may be made of cast metal, such as iron orsteel cast into sheet form with the corrugations formed therein bycasting.

The deeper corrugations 2 form legs which keep the body of the boxbottom spaced above the floor of the annealing furnace so that theheating gases may pass freely under the box. T he legs also permit theready insertion beneath the box eta-he prongs of the usual gooseneck'annealing box lifter.

The metal is of substantially the same thickness throughout the boxbottom, and therefore of substantially the same heat conductivitythroughout, so that there is a substantially even distribution of heatover the entire bottom, and it is thus possible to avoid cold spots suchas are formed when legs or thickened places are formed on the bottom.

shallower corrugations 13 extend at right angles to the corrugations 2.The system of cross corrugations stifi'ens the bottom.

The metal of the bottom is of a thickness substantially the same as orcomparable with that of the annealing box 4 which is indicated in dotand dash lines in Figure 2. A substantially uniform heating of the packof sheets, both too and bottom, is thus permitted. The usual practicehas been to make annealing box bottoms of cast iron, which have beenmuch thicker than the box portion proper, and have therefore required somuch heat to anneal the bottom of the pack that. the top of the pack hasoften been burned before the bottom has been sufficiently annealed.Attempts to remedy this defect, have been made b constructing the bottomof thinner metal with legs riveted or welded thereto. Such legs are aptto burn or scale off, are expensive to apply, and make spots where themass of the metal is increased and is therefore colder than theintermediate portions of the bottom. As can readily beseen, my annealingbox bottom permits ready conductivity of heat to the bottom of the pack,but at the same time it is strong and stiff, has no legs to burn orscale ofi'.'and can be made at. a moderate cost.

While I have specifically illustrated and described a preferredembodiment of my invention, it is' to be understood that the inventionis not limited to its illustrated embodiment but may be embodied inother constructions of annealing box bottoms within the scope of thefollowing claims.

I claim:

1. An annealing box bottom having corrugations forming box supportinglegs for maintaining the body of the box bottom spaced above the floorof the "annealing furnace, there being openings communicating with thespace between the corrugations and the combustion space of the furnacewhen the box is. in the furnace for permitting the access of heatinggases therebeneath, substantially as described.

2. An annealing box bottom having a substantially uniform thickness ofmaterial throughout and having corrugations forming box supporting legsfor maintaining the body of the box bottom spaced above the floor of theannealing furnace there being openings communicating with the spacebetween the corrugations and the combustion space of the furnace whenthe box is in the Q emme furnace for permitting the access of heatinggases therebeneath, end having additional gases therebeneath,substantially as deshallower corrugations for giving additional 10scribed. strength to said box bottom, substantially as 3. An annealingbox bottom having corrudescribed.

5 gations forming box supporting legs for In testimony whereof I havehereunte set maintaining the body of the box bottom my hand. spacedabove the fioor of the annealing furnace and permitting the access ofheating IRVIN F. LEHMAN.

